src/egl/main/eglconfig.c

   1 /**
   2  * EGL Configuration (pixel format) functions.
   3  */
   4
   5
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9 #include <assert.h>
  10 #include "eglconfig.h"
  11 #include "egldisplay.h"
  12 #include "egldriver.h"
  13 #include "eglglobals.h"
  14 #include "egllog.h"
  15
  16
  17 #define MIN2(A, B)  (((A) < (B)) ? (A) : (B))
  18 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
  19
  20
  21 /**
  22  * Init the given _EGLconfig to default values.
  23  * \param id  the configuration's ID.
  24  *
  25  * Note that id must be positive for the config to be valid.
  26  * It is also recommended that when there are N configs, their
  27  * IDs are from 1 to N respectively.
  28  */
  29 void
  30 _eglInitConfig(_EGLConfig *config, EGLint id)
  31 {
  32    memset(config, 0, sizeof(*config));
  33
  34    /* some attributes take non-zero default values */
  35    SET_CONFIG_ATTRIB(config, EGL_CONFIG_ID,               id);
  36    SET_CONFIG_ATTRIB(config, EGL_CONFIG_CAVEAT,           EGL_NONE);
  37    SET_CONFIG_ATTRIB(config, EGL_TRANSPARENT_TYPE,        EGL_NONE);
  38    SET_CONFIG_ATTRIB(config, EGL_NATIVE_VISUAL_TYPE,      EGL_NONE);
  39 #ifdef EGL_VERSION_1_2
  40    SET_CONFIG_ATTRIB(config, EGL_COLOR_BUFFER_TYPE,       EGL_RGB_BUFFER);
  41 #endif /* EGL_VERSION_1_2 */
  42 }
  43
  44
  45 /**
  46  * Link a config to a display and return the handle of the link.
  47  * The handle can be passed to client directly.
  48  *
  49  * Note that we just save the ptr to the config (we don't copy the config).
  50  */
  51 EGLConfig
  52 _eglAddConfig(_EGLDisplay *dpy, _EGLConfig *conf)
  53 {
  54    _EGLConfig **configs;
  55
  56    /* sanity check */
  57    assert(GET_CONFIG_ATTRIB(conf, EGL_CONFIG_ID) > 0);
  58
  59    configs = dpy->Configs;
  60    if (dpy->NumConfigs >= dpy->MaxConfigs) {
  61       EGLint new_size = dpy->MaxConfigs + 16;
  62       assert(dpy->NumConfigs < new_size);
  63
  64       configs = realloc(dpy->Configs, new_size * sizeof(dpy->Configs[0]));
  65       if (!configs)
  66          return (EGLConfig) NULL;
  67
  68       dpy->Configs = configs;
  69       dpy->MaxConfigs = new_size;
  70    }
  71
  72    conf->Display = dpy;
  73    dpy->Configs[dpy->NumConfigs++] = conf;
  74
  75    return (EGLConfig) conf;
  76 }
  77
  78
  79 #ifndef _EGL_SKIP_HANDLE_CHECK
  80
  81
  82 EGLBoolean
  83 _eglCheckConfigHandle(EGLConfig config, _EGLDisplay *dpy)
  84 {
  85    EGLint num_configs = (dpy) ? dpy->NumConfigs : 0;
  86    EGLint i;
  87
  88    for (i = 0; i < num_configs; i++) {
  89       _EGLConfig *conf = dpy->Configs[i];
  90       if (conf == (_EGLConfig *) config) {
  91          assert(conf->Display == dpy);
  92          break;
  93       }
  94    }
  95    return (i < num_configs);
  96 }
  97
  98
  99 #endif /* _EGL_SKIP_HANDLE_CHECK */
 100
 101
 102 enum {
 103    /* types */
 104    ATTRIB_TYPE_INTEGER,
 105    ATTRIB_TYPE_BOOLEAN,
 106    ATTRIB_TYPE_BITMASK,
 107    ATTRIB_TYPE_ENUM,
 108    ATTRIB_TYPE_PSEUDO, /* non-queryable */
 109    ATTRIB_TYPE_PLATFORM, /* platform-dependent */
 110    /* criteria */
 111    ATTRIB_CRITERION_EXACT,
 112    ATTRIB_CRITERION_ATLEAST,
 113    ATTRIB_CRITERION_MASK,
 114    ATTRIB_CRITERION_SPECIAL,
 115    ATTRIB_CRITERION_IGNORE,
 116 };
 117
 118
 119 /* EGL spec Table 3.1 and 3.4 */
 120 static const struct {
 121    EGLint attr;
 122    EGLint type;
 123    EGLint criterion;
 124    EGLint default_value;
 125 } _eglValidationTable[] =
 126 {
 127    { EGL_BUFFER_SIZE,               ATTRIB_TYPE_INTEGER,
 128                                     ATTRIB_CRITERION_ATLEAST,
 129                                     0 },
 130    { EGL_RED_SIZE,                  ATTRIB_TYPE_INTEGER,
 131                                     ATTRIB_CRITERION_ATLEAST,
 132                                     0 },
 133    { EGL_GREEN_SIZE,                ATTRIB_TYPE_INTEGER,
 134                                     ATTRIB_CRITERION_ATLEAST,
 135                                     0 },
 136    { EGL_BLUE_SIZE,                 ATTRIB_TYPE_INTEGER,
 137                                     ATTRIB_CRITERION_ATLEAST,
 138                                     0 },
 139    { EGL_LUMINANCE_SIZE,            ATTRIB_TYPE_INTEGER,
 140                                     ATTRIB_CRITERION_ATLEAST,
 141                                     0 },
 142    { EGL_ALPHA_SIZE,                ATTRIB_TYPE_INTEGER,
 143                                     ATTRIB_CRITERION_ATLEAST,
 144                                     0 },
 145    { EGL_ALPHA_MASK_SIZE,           ATTRIB_TYPE_INTEGER,
 146                                     ATTRIB_CRITERION_ATLEAST,
 147                                     0 },
 148    { EGL_BIND_TO_TEXTURE_RGB,       ATTRIB_TYPE_BOOLEAN,
 149                                     ATTRIB_CRITERION_EXACT,
 150                                     EGL_DONT_CARE },
 151    { EGL_BIND_TO_TEXTURE_RGBA,      ATTRIB_TYPE_BOOLEAN,
 152                                     ATTRIB_CRITERION_EXACT,
 153                                     EGL_DONT_CARE },
 154    { EGL_COLOR_BUFFER_TYPE,         ATTRIB_TYPE_ENUM,
 155                                     ATTRIB_CRITERION_EXACT,
 156                                     EGL_RGB_BUFFER },
 157    { EGL_CONFIG_CAVEAT,             ATTRIB_TYPE_ENUM,
 158                                     ATTRIB_CRITERION_EXACT,
 159                                     EGL_DONT_CARE },
 160    { EGL_CONFIG_ID,                 ATTRIB_TYPE_INTEGER,
 161                                     ATTRIB_CRITERION_EXACT,
 162                                     EGL_DONT_CARE },
 163    { EGL_CONFORMANT,                ATTRIB_TYPE_BITMASK,
 164                                     ATTRIB_CRITERION_MASK,
 165                                     0 },
 166    { EGL_DEPTH_SIZE,                ATTRIB_TYPE_INTEGER,
 167                                     ATTRIB_CRITERION_ATLEAST,
 168                                     0 },
 169    { EGL_LEVEL,                     ATTRIB_TYPE_PLATFORM,
 170                                     ATTRIB_CRITERION_EXACT,
 171                                     0 },
 172    { EGL_MAX_PBUFFER_WIDTH,         ATTRIB_TYPE_INTEGER,
 173                                     ATTRIB_CRITERION_IGNORE,
 174                                     0 },
 175    { EGL_MAX_PBUFFER_HEIGHT,        ATTRIB_TYPE_INTEGER,
 176                                     ATTRIB_CRITERION_IGNORE,
 177                                     0 },
 178    { EGL_MAX_PBUFFER_PIXELS,        ATTRIB_TYPE_INTEGER,
 179                                     ATTRIB_CRITERION_IGNORE,
 180                                     0 },
 181    { EGL_MAX_SWAP_INTERVAL,         ATTRIB_TYPE_INTEGER,
 182                                     ATTRIB_CRITERION_EXACT,
 183                                     EGL_DONT_CARE },
 184    { EGL_MIN_SWAP_INTERVAL,         ATTRIB_TYPE_INTEGER,
 185                                     ATTRIB_CRITERION_EXACT,
 186                                     EGL_DONT_CARE },
 187    { EGL_NATIVE_RENDERABLE,         ATTRIB_TYPE_BOOLEAN,
 188                                     ATTRIB_CRITERION_EXACT,
 189                                     EGL_DONT_CARE },
 190    { EGL_NATIVE_VISUAL_ID,          ATTRIB_TYPE_PLATFORM,
 191                                     ATTRIB_CRITERION_IGNORE,
 192                                     0 },
 193    { EGL_NATIVE_VISUAL_TYPE,        ATTRIB_TYPE_PLATFORM,
 194                                     ATTRIB_CRITERION_EXACT,
 195                                     EGL_DONT_CARE },
 196    { EGL_RENDERABLE_TYPE,           ATTRIB_TYPE_BITMASK,
 197                                     ATTRIB_CRITERION_MASK,
 198                                     EGL_OPENGL_ES_BIT },
 199    { EGL_SAMPLE_BUFFERS,            ATTRIB_TYPE_INTEGER,
 200                                     ATTRIB_CRITERION_ATLEAST,
 201                                     0 },
 202    { EGL_SAMPLES,                   ATTRIB_TYPE_INTEGER,
 203                                     ATTRIB_CRITERION_ATLEAST,
 204                                     0 },
 205    { EGL_STENCIL_SIZE,              ATTRIB_TYPE_INTEGER,
 206                                     ATTRIB_CRITERION_ATLEAST,
 207                                     0 },
 208    { EGL_SURFACE_TYPE,              ATTRIB_TYPE_BITMASK,
 209                                     ATTRIB_CRITERION_MASK,
 210                                     EGL_WINDOW_BIT },
 211    { EGL_TRANSPARENT_TYPE,          ATTRIB_TYPE_ENUM,
 212                                     ATTRIB_CRITERION_EXACT,
 213                                     EGL_NONE },
 214    { EGL_TRANSPARENT_RED_VALUE,     ATTRIB_TYPE_INTEGER,
 215                                     ATTRIB_CRITERION_EXACT,
 216                                     EGL_DONT_CARE },
 217    { EGL_TRANSPARENT_GREEN_VALUE,   ATTRIB_TYPE_INTEGER,
 218                                     ATTRIB_CRITERION_EXACT,
 219                                     EGL_DONT_CARE },
 220    { EGL_TRANSPARENT_BLUE_VALUE,    ATTRIB_TYPE_INTEGER,
 221                                     ATTRIB_CRITERION_EXACT,
 222                                     EGL_DONT_CARE },
 223    /* these are not real attributes */
 224    { EGL_MATCH_NATIVE_PIXMAP,       ATTRIB_TYPE_PSEUDO,
 225                                     ATTRIB_CRITERION_SPECIAL,
 226                                     EGL_NONE },
 227    { EGL_PRESERVED_RESOURCES,       ATTRIB_TYPE_PSEUDO,
 228                                     ATTRIB_CRITERION_IGNORE,
 229                                     0 },
 230    { EGL_NONE,                      ATTRIB_TYPE_PSEUDO,
 231                                     ATTRIB_CRITERION_IGNORE,
 232                                     0 }
 233 };
 234
 235
 236 /**
 237  * Return true if a config is valid.  When for_matching is true,
 238  * EGL_DONT_CARE is accepted as a valid attribute value, and checks
 239  * for conflicting attribute values are skipped.
 240  *
 241  * Note that some attributes are platform-dependent and are not
 242  * checked.
 243  */
 244 EGLBoolean
 245 _eglValidateConfig(const _EGLConfig *conf, EGLBoolean for_matching)
 246 {
 247    EGLint i, attr, val;
 248    EGLBoolean valid = EGL_TRUE;
 249    EGLint red_size = 0, green_size = 0, blue_size = 0, luminance_size = 0;
 250    EGLint alpha_size = 0, buffer_size = 0;
 251
 252    /* all attributes should have been listed */
 253    assert(ARRAY_SIZE(_eglValidationTable) == _EGL_CONFIG_NUM_ATTRIBS);
 254
 255    /* check attributes by their types */
 256    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
 257       EGLint mask;
 258
 259       attr = _eglValidationTable[i].attr;
 260       val = GET_CONFIG_ATTRIB(conf, attr);
 261
 262       switch (_eglValidationTable[i].type) {
 263       case ATTRIB_TYPE_INTEGER:
 264          switch (attr) {
 265          case EGL_CONFIG_ID:
 266             /* config id must be positive */
 267             if (val <= 0)
 268                valid = EGL_FALSE;
 269             break;
 270          case EGL_SAMPLE_BUFFERS:
 271             /* there can be at most 1 sample buffer */
 272             if (val > 1)
 273                valid = EGL_FALSE;
 274             break;
 275          case EGL_RED_SIZE:
 276             red_size = val;
 277             break;
 278          case EGL_GREEN_SIZE:
 279             green_size = val;
 280             break;
 281          case EGL_BLUE_SIZE:
 282             blue_size = val;
 283             break;
 284          case EGL_LUMINANCE_SIZE:
 285             luminance_size = val;
 286             break;
 287          case EGL_ALPHA_SIZE:
 288             alpha_size = val;
 289             break;
 290          case EGL_BUFFER_SIZE:
 291             buffer_size = val;
 292             break;
 293          }
 294          if (val < 0)
 295             valid = EGL_FALSE;
 296          break;
 297       case ATTRIB_TYPE_BOOLEAN:
 298          if (val != EGL_TRUE && val != EGL_FALSE)
 299             valid = EGL_FALSE;
 300          break;
 301       case ATTRIB_TYPE_ENUM:
 302          switch (attr) {
 303          case EGL_CONFIG_CAVEAT:
 304             if (val != EGL_NONE && val != EGL_SLOW_CONFIG &&
 305                 val != EGL_NON_CONFORMANT_CONFIG)
 306                valid = EGL_FALSE;
 307             break;
 308          case EGL_TRANSPARENT_TYPE:
 309             if (val != EGL_NONE && val != EGL_TRANSPARENT_RGB)
 310                valid = EGL_FALSE;
 311             break;
 312          case EGL_COLOR_BUFFER_TYPE:
 313             if (val != EGL_RGB_BUFFER && val != EGL_LUMINANCE_BUFFER)
 314                valid = EGL_FALSE;
 315             break;
 316          default:
 317             assert(0);
 318             break;
 319          }
 320          break;
 321       case ATTRIB_TYPE_BITMASK:
 322          switch (attr) {
 323          case EGL_SURFACE_TYPE:
 324             mask = EGL_PBUFFER_BIT |
 325                    EGL_PIXMAP_BIT |
 326                    EGL_WINDOW_BIT |
 327                    EGL_VG_COLORSPACE_LINEAR_BIT |
 328                    EGL_VG_ALPHA_FORMAT_PRE_BIT |
 329                    EGL_MULTISAMPLE_RESOLVE_BOX_BIT |
 330                    EGL_SWAP_BEHAVIOR_PRESERVED_BIT;
 331             break;
 332          case EGL_RENDERABLE_TYPE:
 333          case EGL_CONFORMANT:
 334             mask = EGL_OPENGL_ES_BIT |
 335                    EGL_OPENVG_BIT |
 336                    EGL_OPENGL_ES2_BIT |
 337                    EGL_OPENGL_BIT;
 338             break;
 339          default:
 340             assert(0);
 341             break;
 342          }
 343          if (val & ~mask)
 344             valid = EGL_FALSE;
 345          break;
 346       case ATTRIB_TYPE_PLATFORM:
 347          /* unable to check platform-dependent attributes here */
 348          break;
 349       case ATTRIB_TYPE_PSEUDO:
 350          /* pseudo attributes should not be set */
 351          if (val != 0)
 352             valid = EGL_FALSE;
 353          break;
 354       default:
 355          assert(0);
 356          break;
 357       }
 358
 359       if (!valid && for_matching) {
 360          /* accept EGL_DONT_CARE as a valid value */
 361          if (val == EGL_DONT_CARE)
 362             valid = EGL_TRUE;
 363          if (_eglValidationTable[i].criterion == ATTRIB_CRITERION_SPECIAL)
 364             valid = EGL_TRUE;
 365       }
 366       if (!valid)
 367          break;
 368    }
 369
 370    /* any invalid attribute value should have been catched */
 371    if (!valid || for_matching)
 372       return valid;
 373
 374    /* now check for conflicting attribute values */
 375
 376    switch (GET_CONFIG_ATTRIB(conf, EGL_COLOR_BUFFER_TYPE)) {
 377    case EGL_RGB_BUFFER:
 378       if (luminance_size)
 379          valid = EGL_FALSE;
 380       if (red_size + green_size + blue_size + alpha_size != buffer_size)
 381          valid = EGL_FALSE;
 382       break;
 383    case EGL_LUMINANCE_BUFFER:
 384       if (red_size || green_size || blue_size)
 385          valid = EGL_FALSE;
 386       if (luminance_size + alpha_size != buffer_size)
 387          valid = EGL_FALSE;
 388       break;
 389    }
 390
 391    val = GET_CONFIG_ATTRIB(conf, EGL_SAMPLE_BUFFERS);
 392    if (!val && GET_CONFIG_ATTRIB(conf, EGL_SAMPLES))
 393       valid = EGL_FALSE;
 394
 395    val = GET_CONFIG_ATTRIB(conf, EGL_SURFACE_TYPE);
 396    if (!(val & EGL_WINDOW_BIT)) {
 397       if (GET_CONFIG_ATTRIB(conf, EGL_NATIVE_VISUAL_ID) != 0 ||
 398           GET_CONFIG_ATTRIB(conf, EGL_NATIVE_VISUAL_TYPE) != EGL_NONE)
 399          valid = EGL_FALSE;
 400    }
 401    if (!(val & EGL_PBUFFER_BIT)) {
 402       if (GET_CONFIG_ATTRIB(conf, EGL_BIND_TO_TEXTURE_RGB) ||
 403           GET_CONFIG_ATTRIB(conf, EGL_BIND_TO_TEXTURE_RGBA))
 404          valid = EGL_FALSE;
 405    }
 406
 407    return valid;
 408 }
 409
 410
 411 /**
 412  * Return true if a config matches the criteria.  This and
 413  * _eglParseConfigAttribList together implement the algorithm
 414  * described in "Selection of EGLConfigs".
 415  *
 416  * Note that attributes that are special (currently, only
 417  * EGL_MATCH_NATIVE_PIXMAP) are ignored.
 418  */
 419 EGLBoolean
 420 _eglMatchConfig(const _EGLConfig *conf, const _EGLConfig *criteria)
 421 {
 422    EGLint attr, val, i;
 423    EGLBoolean matched = EGL_TRUE;
 424
 425    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
 426       EGLint cmp;
 427       if (_eglValidationTable[i].criterion == ATTRIB_CRITERION_IGNORE)
 428          continue;
 429
 430       attr = _eglValidationTable[i].attr;
 431       cmp = GET_CONFIG_ATTRIB(criteria, attr);
 432       if (cmp == EGL_DONT_CARE)
 433          continue;
 434
 435       val = GET_CONFIG_ATTRIB(conf, attr);
 436       switch (_eglValidationTable[i].criterion) {
 437       case ATTRIB_CRITERION_EXACT:
 438          if (val != cmp)
 439             matched = EGL_FALSE;
 440          break;
 441       case ATTRIB_CRITERION_ATLEAST:
 442          if (val < cmp)
 443             matched = EGL_FALSE;
 444          break;
 445       case ATTRIB_CRITERION_MASK:
 446          if ((val & cmp) != cmp)
 447             matched = EGL_FALSE;
 448          break;
 449       case ATTRIB_CRITERION_SPECIAL:
 450          /* ignored here */
 451          break;
 452       default:
 453          assert(0);
 454          break;
 455       }
 456
 457       if (!matched)
 458          break;
 459    }
 460
 461    return matched;
 462 }
 463
 464
 465 /**
 466  * Initialize a criteria config from the given attribute list.
 467  * Return EGL_FALSE if any of the attribute is invalid.
 468  */
 469 EGLBoolean
 470 _eglParseConfigAttribList(_EGLConfig *conf, const EGLint *attrib_list)
 471 {
 472    EGLint attr, val, i;
 473    EGLint config_id = 0, level = 0;
 474    EGLBoolean has_native_visual_type = EGL_FALSE;
 475    EGLBoolean has_transparent_color = EGL_FALSE;
 476
 477    /* reset to default values */
 478    for (i = 0; i < ARRAY_SIZE(_eglValidationTable); i++) {
 479       attr = _eglValidationTable[i].attr;
 480       val = _eglValidationTable[i].default_value;
 481       SET_CONFIG_ATTRIB(conf, attr, val);
 482    }
 483
 484    /* parse the list */
 485    for (i = 0; attrib_list && attrib_list[i] != EGL_NONE; i += 2) {
 486       EGLint idx;
 487
 488       attr = attrib_list[i];
 489       val = attrib_list[i + 1];
 490
 491       idx = _eglIndexConfig(conf, attr);
 492       if (idx < 0)
 493          return EGL_FALSE;
 494       conf->Storage[idx] = val;
 495
 496       /* rememeber some attributes for post-processing */
 497       switch (attr) {
 498       case EGL_CONFIG_ID:
 499          config_id = val;
 500          break;
 501       case EGL_LEVEL:
 502          level = val;
 503          break;
 504       case EGL_NATIVE_VISUAL_TYPE:
 505          has_native_visual_type = EGL_TRUE;
 506          break;
 507       case EGL_TRANSPARENT_RED_VALUE:
 508       case EGL_TRANSPARENT_GREEN_VALUE:
 509       case EGL_TRANSPARENT_BLUE_VALUE:
 510          has_transparent_color = EGL_TRUE;
 511          break;
 512       default:
 513          break;
 514       }
 515    }
 516
 517    if (!_eglValidateConfig(conf, EGL_TRUE))
 518       return EGL_FALSE;
 519
 520    /* the spec says that EGL_LEVEL cannot be EGL_DONT_CARE */
 521    if (level == EGL_DONT_CARE)
 522       return EGL_FALSE;
 523
 524    /* ignore other attributes when EGL_CONFIG_ID is given */
 525    if (config_id > 0) {
 526       _eglResetConfigKeys(conf, EGL_DONT_CARE);
 527       SET_CONFIG_ATTRIB(conf, EGL_CONFIG_ID, config_id);
 528    }
 529    else {
 530       if (has_native_visual_type) {
 531          val = GET_CONFIG_ATTRIB(conf, EGL_SURFACE_TYPE);
 532          if (!(val & EGL_WINDOW_BIT))
 533             SET_CONFIG_ATTRIB(conf, EGL_NATIVE_VISUAL_TYPE, EGL_DONT_CARE);
 534       }
 535
 536       if (has_transparent_color) {
 537          val = GET_CONFIG_ATTRIB(conf, EGL_TRANSPARENT_TYPE);
 538          if (val == EGL_NONE) {
 539             SET_CONFIG_ATTRIB(conf, EGL_TRANSPARENT_RED_VALUE,
 540                               EGL_DONT_CARE);
 541             SET_CONFIG_ATTRIB(conf, EGL_TRANSPARENT_GREEN_VALUE,
 542                               EGL_DONT_CARE);
 543             SET_CONFIG_ATTRIB(conf, EGL_TRANSPARENT_BLUE_VALUE,
 544                               EGL_DONT_CARE);
 545          }
 546       }
 547    }
 548
 549    return EGL_TRUE;
 550 }
 551
 552
 553 /**
 554  * Decide the ordering of conf1 and conf2, under the given criteria.
 555  * When compare_id is true, this implements the algorithm described
 556  * in "Sorting of EGLConfigs".  When compare_id is false,
 557  * EGL_CONFIG_ID is not compared.
 558  *
 559  * It returns a negative integer if conf1 is considered to come
 560  * before conf2;  a positive integer if conf2 is considered to come
 561  * before conf1;  zero if the ordering cannot be decided.
 562  *
 563  * Note that EGL_NATIVE_VISUAL_TYPE is platform-dependent and is
 564  * ignored here.
 565  */
 566 EGLint
 567 _eglCompareConfigs(const _EGLConfig *conf1, const _EGLConfig *conf2,
 568                    const _EGLConfig *criteria, EGLBoolean compare_id)
 569 {
 570    const EGLint compare_attribs[] = {
 571       EGL_BUFFER_SIZE,
 572       EGL_SAMPLE_BUFFERS,
 573       EGL_SAMPLES,
 574       EGL_DEPTH_SIZE,
 575       EGL_STENCIL_SIZE,
 576       EGL_ALPHA_MASK_SIZE,
 577    };
 578    EGLint val1, val2;
 579    EGLBoolean rgb_buffer;
 580    EGLint i;
 581
 582    if (conf1 == conf2)
 583       return 0;
 584
 585    /* the enum values have the desired ordering */
 586    assert(EGL_NONE < EGL_SLOW_CONFIG);
 587    assert(EGL_SLOW_CONFIG < EGL_NON_CONFORMANT_CONFIG);
 588    val1 = GET_CONFIG_ATTRIB(conf1, EGL_CONFIG_CAVEAT);
 589    val2 = GET_CONFIG_ATTRIB(conf2, EGL_CONFIG_CAVEAT);
 590    if (val1 != val2)
 591       return (val1 - val2);
 592
 593    /* the enum values have the desired ordering */
 594    assert(EGL_RGB_BUFFER < EGL_LUMINANCE_BUFFER);
 595    val1 = GET_CONFIG_ATTRIB(conf1, EGL_COLOR_BUFFER_TYPE);
 596    val2 = GET_CONFIG_ATTRIB(conf2, EGL_COLOR_BUFFER_TYPE);
 597    if (val1 != val2)
 598       return (val1 - val2);
 599    rgb_buffer = (val1 == EGL_RGB_BUFFER);
 600
 601    if (criteria) {
 602       val1 = val2 = 0;
 603       if (rgb_buffer) {
 604          if (GET_CONFIG_ATTRIB(criteria, EGL_RED_SIZE) > 0) {
 605             val1 += GET_CONFIG_ATTRIB(conf1, EGL_RED_SIZE);
 606             val2 += GET_CONFIG_ATTRIB(conf2, EGL_RED_SIZE);
 607          }
 608          if (GET_CONFIG_ATTRIB(criteria, EGL_GREEN_SIZE) > 0) {
 609             val1 += GET_CONFIG_ATTRIB(conf1, EGL_GREEN_SIZE);
 610             val2 += GET_CONFIG_ATTRIB(conf2, EGL_GREEN_SIZE);
 611          }
 612          if (GET_CONFIG_ATTRIB(criteria, EGL_BLUE_SIZE) > 0) {
 613             val1 += GET_CONFIG_ATTRIB(conf1, EGL_BLUE_SIZE);
 614             val2 += GET_CONFIG_ATTRIB(conf2, EGL_BLUE_SIZE);
 615          }
 616       }
 617       else {
 618          if (GET_CONFIG_ATTRIB(criteria, EGL_LUMINANCE_SIZE) > 0) {
 619             val1 += GET_CONFIG_ATTRIB(conf1, EGL_LUMINANCE_SIZE);
 620             val2 += GET_CONFIG_ATTRIB(conf2, EGL_LUMINANCE_SIZE);
 621          }
 622       }
 623       if (GET_CONFIG_ATTRIB(criteria, EGL_ALPHA_SIZE) > 0) {
 624          val1 += GET_CONFIG_ATTRIB(conf1, EGL_ALPHA_SIZE);
 625          val2 += GET_CONFIG_ATTRIB(conf2, EGL_ALPHA_SIZE);
 626       }
 627    }
 628    else {
 629       /* assume the default criteria, which gives no specific ordering */
 630       val1 = val2 = 0;
 631    }
 632
 633    /* for color bits, larger one is preferred */
 634    if (val1 != val2)
 635       return (val2 - val1);
 636
 637    for (i = 0; i < ARRAY_SIZE(compare_attribs); i++) {
 638       val1 = GET_CONFIG_ATTRIB(conf1, compare_attribs[i]);
 639       val2 = GET_CONFIG_ATTRIB(conf2, compare_attribs[i]);
 640       if (val1 != val2)
 641          return (val1 - val2);
 642    }
 643
 644    /* EGL_NATIVE_VISUAL_TYPE cannot be compared here */
 645
 646    if (compare_id) {
 647       val1 = GET_CONFIG_ATTRIB(conf1, EGL_CONFIG_ID);
 648       val2 = GET_CONFIG_ATTRIB(conf2, EGL_CONFIG_ID);
 649       assert(val1 != val2);
 650    }
 651    else {
 652       val1 = val2 = 0;
 653    }
 654
 655    return (val1 - val2);
 656 }
 657
 658
 659 static INLINE
 660 void _eglSwapConfigs(const _EGLConfig **conf1, const _EGLConfig **conf2)
 661 {
 662    const _EGLConfig *tmp = *conf1;
 663    *conf1 = *conf2;
 664    *conf2 = tmp;
 665 }
 666
 667
 668 /**
 669  * Quick sort an array of configs.  This differs from the standard
 670  * qsort() in that the compare function accepts an additional
 671  * argument.
 672  */
 673 void
 674 _eglSortConfigs(const _EGLConfig **configs, EGLint count,
 675                 EGLint (*compare)(const _EGLConfig *, const _EGLConfig *,
 676                                   void *),
 677                 void *priv_data)
 678 {
 679    const EGLint pivot = 0;
 680    EGLint i, j;
 681
 682    if (count <= 1)
 683       return;
 684
 685    _eglSwapConfigs(&configs[pivot], &configs[count / 2]);
 686    i = 1;
 687    j = count - 1;
 688    do {
 689       while (i < count && compare(configs[i], configs[pivot], priv_data) < 0)
 690          i++;
 691       while (compare(configs[j], configs[pivot], priv_data) > 0)
 692          j--;
 693       if (i < j) {
 694          _eglSwapConfigs(&configs[i], &configs[j]);
 695          i++;
 696          j--;
 697       }
 698       else if (i == j) {
 699          i++;
 700          j--;
 701          break;
 702       }
 703    } while (i <= j);
 704    _eglSwapConfigs(&configs[pivot], &configs[j]);
 705
 706    _eglSortConfigs(configs, j, compare, priv_data);
 707    _eglSortConfigs(configs + i, count - i, compare, priv_data);
 708 }
 709
 710
 711 static int
 712 _eglFallbackCompare(const _EGLConfig *conf1, const _EGLConfig *conf2,
 713                    void *priv_data)
 714 {
 715    const _EGLConfig *criteria = (const _EGLConfig *) priv_data;
 716    return _eglCompareConfigs(conf1, conf2, criteria, EGL_TRUE);
 717 }
 718
 719
 720 /**
 721  * Typical fallback routine for eglChooseConfig
 722  */
 723 EGLBoolean
 724 _eglChooseConfig(_EGLDriver *drv, _EGLDisplay *disp, const EGLint *attrib_list,
 725                  EGLConfig *configs, EGLint config_size, EGLint *num_configs)
 726 {
 727    _EGLConfig **configList, criteria;
 728    EGLint i, count;
 729
 730    if (!num_configs)
 731       return _eglError(EGL_BAD_PARAMETER, "eglChooseConfigs");
 732
 733    _eglInitConfig(&criteria, 0);
 734    if (!_eglParseConfigAttribList(&criteria, attrib_list))
 735       return _eglError(EGL_BAD_ATTRIBUTE, "eglChooseConfig");
 736
 737    /* allocate array of config pointers */
 738    configList = (_EGLConfig **)
 739       malloc(disp->NumConfigs * sizeof(_EGLConfig *));
 740    if (!configList)
 741       return _eglError(EGL_BAD_ALLOC, "eglChooseConfig(out of memory)");
 742
 743    /* perform selection of configs */
 744    count = 0;
 745    for (i = 0; i < disp->NumConfigs; i++) {
 746       if (_eglMatchConfig(disp->Configs[i], &criteria))
 747          configList[count++] = disp->Configs[i];
 748    }
 749
 750    /* perform sorting of configs */
 751    if (configs && count) {
 752       _eglSortConfigs((const _EGLConfig **) configList, count,
 753                       _eglFallbackCompare, (void *) &criteria);
 754       count = MIN2(count, config_size);
 755       for (i = 0; i < count; i++)
 756          configs[i] = _eglGetConfigHandle(configList[i]);
 757    }
 758
 759    free(configList);
 760
 761    *num_configs = count;
 762
 763    return EGL_TRUE;
 764 }
 765
 766
 767 static INLINE EGLBoolean
 768 _eglIsConfigAttribValid(_EGLConfig *conf, EGLint attr)
 769 {
 770    if (_eglIndexConfig(conf, attr) < 0)
 771       return EGL_FALSE;
 772
 773    /* there are some holes in the range */
 774    switch (attr) {
 775    case EGL_PRESERVED_RESOURCES:
 776    case EGL_NONE:
 777 #ifdef EGL_VERSION_1_4
 778    case EGL_MATCH_NATIVE_PIXMAP:
 779 #endif
 780       return EGL_FALSE;
 781    default:
 782       break;
 783    }
 784
 785    return EGL_TRUE;
 786 }
 787
 788
 789 /**
 790  * Fallback for eglGetConfigAttrib.
 791  */
 792 EGLBoolean
 793 _eglGetConfigAttrib(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *conf,
 794                     EGLint attribute, EGLint *value)
 795 {
 796    if (!_eglIsConfigAttribValid(conf, attribute))
 797       return _eglError(EGL_BAD_ATTRIBUTE, "eglGetConfigAttrib");
 798    if (!value)
 799       return _eglError(EGL_BAD_PARAMETER, "eglGetConfigAttrib");
 800
 801    *value = GET_CONFIG_ATTRIB(conf, attribute);
 802    return EGL_TRUE;
 803 }
 804
 805
 806 /**
 807  * Fallback for eglGetConfigs.
 808  */
 809 EGLBoolean
 810 _eglGetConfigs(_EGLDriver *drv, _EGLDisplay *disp, EGLConfig *configs,
 811                EGLint config_size, EGLint *num_config)
 812 {
 813    if (!num_config)
 814       return _eglError(EGL_BAD_PARAMETER, "eglGetConfigs");
 815
 816    if (configs) {
 817       EGLint i;
 818       *num_config = MIN2(disp->NumConfigs, config_size);
 819       for (i = 0; i < *num_config; i++)
 820          configs[i] = _eglGetConfigHandle(disp->Configs[i]);
 821    }
 822    else {
 823       /* just return total number of supported configs */
 824       *num_config = disp->NumConfigs;
 825    }
 826
 827    return EGL_TRUE;
 828 }